Installation for the automatic operation of hydraulic presses in a predetermined and continuous succession of working cycles



March 5, 1963 A. VITALI 3,079,857

INSTALLATION FOR THE AUTOMATIC OPERATION OF HYDRAULIC PRESSES IN A PREDETERMINED AND CONTINUOUS SUCCESSION 0F WORKING CYCLES Filed Aug. 3, 1959 8 Sheets-Sheet 1 Q INVENTOR. W W0.

BY 'H'J Q $.M4...

March 5, 1963 A. VITALI ,85

INSTALLATION FOR THE AUTOMATIC OPERATION OF HYDRAULIC PRESSES IN A PREDETERMINED AND CONTINUOUS SUCCESSION OF WORKING CYCLES Filed Aug- 5, 1959 8 Sheets-Sheet 2 INVENTOR.

March 5, 1963 A; VITAL] 3,079,857

INSTALLATION FOR THE AUT MATIC OPERATION OF HYDRAULIC v PRESSES IN A PREDETERMINED AND CGNTINUOUS SUCCESSION 0F WORKING CYCLES Filed Aug. 5, 1959' 8 Sheets-Sheet 3 March 5, 1963 VITAL] 3,079,857

A. INSTALLATION FOR THE AUTOMATIC OPERATION OF HYDRAULIC PRESSES IN A PREDETERMINED AND CONTINUOUS SUCCESSION OF WORKING CYCLES Filed Aug. 3, 1959 8 Sheets-Sheet 4 b Q INVENTOR.

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3,079,857 RAULIC March 5, 1963 A. VlTALl INSTALLATION FOR THE AUTOMATIC OPERATION OF HYD PRESSES IN A PREDETERMINED AND CONTINUOUS SUCCESSION OF WORKING CYCLES 8 Sheets-Sheet 5 Filed Aug. 3, 1959 INVENTOR.

A. VITALI INSTALLATION FOR THE AUTOMATIC OPERATION OF HYDRAULIC PRESSES IN A PREDETERMINED AND CONTINUOUS SUCCESSION OF WORKING CYCLES March 5, 1963 Filed Au 3, 1959 March 5, 1963 A. VITAL] 3,07

INSTALLATION FOR THE AUTOMATIC OPERATION OF HYDRAULIC PRESSES IN A PREDETERMINED AND CONTINUOUS SUCCESSION OF WORKING CYCLES Filed Aug. 3, 1959 8 Sheets-Sheet 7 INVENTOR. 2 Q

I N2 We March 5, 1963 A. VITAL] 3,07

INSTALLATION FOR THE AUTOMATIC OPERATION OF HYDRAULIC PRESSES IN A PREDETERMINED AND CONTINUOUS SUCCESSION 0F WORKING CYCLES Filed Aug. 3, 1959 8 Sheets-Sheet 8 INVENTOR.

CWT-n 4 United States Patent C 3,079,857 INSTALLATIQN 159R THE; AUTQMATIQ (HERA- TIQN F- PR-ESSES IN. A FREDE- TERMINED. AND CONTINUOUS-SUCCESSIQN. 0F WORKING CYCLES Antonio Vitali, Milan, Italy, assignor to SA. Macchme lmlustria Dulciaria Carle '& Montanari, Milan, Italy, a corporation of Italy Filed Aug. 3, 1959, Ser. No. 831,347 Claims priority, application Italy Apr. 11 1959. 14' (Iiairns. (Cl. tan-P53):

The present invention relates to an installation for the automatic operation of hydraulic presses, in a predetermined and continuous succession of working cycles.

Filter presses are already known which are combined with ahydraulic press, and comprise a series of cylindrical chambers with filtering plates formed as pistons; each plate, together with a surrounding ring, constitutes a, cyl'indrical press or squeezing chamber; the chambers are opened and. closed together, by relative displacement between the surrounding rings and the filtering plates which are formed as pistons; the chambers are opened by means of stepped rods which are axially displaceable for the expulsion of cakes of pressed cocoa beans, and are closed by suitable springs pulling the surrounding rings back into the initial position.

It is also known that in presses of this type the feeding of the material to be pressed is eifected by pumpingthis material, which is in a more or less fluid state, at an appropriate initial pressure; the material is then pressed or squeezed in the cylindrical chambers arranged in a row, by the action. of the pressure exerted, by the hydraulically actuated main thrust plunger, on the first piston of these chambers and consequently on the other pistons of the chambers for pressing the fluid substance, as a result of the decrease in the volume of these chambers; the liquid, expelled from the material is deliveredfrom these chamhers into a collecting container disposed underneath, whereas the cakes of residual material compressed in the disc-shaped chambers are removed or caused to fall under their own weight when pressing has been completed; means are, provided whereby the. chambers of all the units are all opened together; after discharge has taken place, the chambers are closed again by means of known compression' springs, and again form cylindrical cavities to receive further material to be subjected to pressing, thereby permitting; repetition ofthe' Working cycle.

It is also known that the output of such presses is directlyproportional to the quantity of liquid extracted, i.e. to predetermined minimum percentage of liquid left in the residual material pressed into the form of cakes, and secondly to the time required for completing each working cycle during which liquid is squeezed out and the residual material is expelled after having been pressed into the form of disc-shaped cakes. I

Applicant has also disclosed apparatus provided with a suitable pneumatically operating device for charging or admitting the'fi'uid substance, which is to be pressed, into the cylindricalpressing chambers; this device is adapted to ensure the required supply of the fluid substance to be pressed." p

Lastly, applicant has also disclosed a press of this type, which has two series of multiple pressing chambers. dis.- posed'coaxially and interconnected by a central'body comprising two cylinders each provided 'with a hydraulic thrust plunger for a respective one. of the two series of filter plate pistons of the multiple pressing chambers; these thrust. plunger-s are so disposed as to exert the thrust in the sme direction but in opposite senses. on the pistons provided with filter plates and belonging to the respective series of multiple pressure chambers,

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A principal object which an installation constructed in accordance with the present invention is intended to achieve, is topermit the automatic operation of the installation to be interrupted by hand atany moment when it may be found necessary to intervene immediately in order to prevent something undesirable from occurring.

Another object at which the invention aims is to make certain, in every case, of the required succession of the various steps needed in" order to-obtain a' complete working cycle; this may fail to occur if each of the operations has to be performed under manual control.

Another object which the invention seeks to attain, is to make it possible to have timely warning of any damage or irregularity that may occur during'the operation of the press since such disturbances may sometimes have serious undesirable consequences, for instance if untimely opening of the cylindrical chambers takes place, when they are filled, instead of the; pressing step. In this case the hum mass, which often amounts to several'hundred weight and is at a temperature of about would be discharged, and the results would of course be serious.

These and other objects are achieved by the installation, designed in accordance with the present invention, for the automatic operation. oi hydraulic presses of the above mentioned type and other similar presses in order to obtain a predetermined and continuous succession of working cycles. One embodiment of the installation is characterised in that it comprises, in combination with a hydraulically operated press having a plurality of cylindrical chambers with filtering plates in the form of pistons sliding withincorresponding cylinders in the form of surrounding rings to press the fluid substance, an agitator in which the substance is previously treated before being introduced into a device for measuring the pre deter-mined quantity ofsubstance to be introduced into the chambers for pressing this substance, a measuring and precharging device into which the fluid substance is introduced after leaving the agitator, a pump, associated with a motor, for withdrawing the treated material from the agitator and introducing the material into the measuring device which is provided with a device for interruptingthe admission of the fluid substance, withdrawn from the agitator, as soon as the pre'd'etermined'quanti'ty to be contained-in the measuring device has been reached, and with a device for stopping the pump which withdrawsthe fluid sub stance from the measuring device and introduces the substance into a distributor distributing the substance to the pressing chambers, a switch member disposed on a control panel ot'the machine and adapted to be actuated to start the installation after the measuring device has been charged, to obtain automatic or manual operation of the installation, a compressor for producing compressed air required for the operation of the installation, a device adaptedto cause discharge of compressed air taken from the compressor to act on valves of a pneumatically op erating device for controlling the admission of. the material-to eachpressing chamber, which valves however are also adapted to prevent the fluidsubstance from entering the respective cylindrical pressing chamber, this discharge device being arranged to'corne into. operation as soon as the measuring device has been completely charged, a pump driven'by a motor and performing the function of withdrawing the material from the measuring device and charging the material into the pressing chambers, which pump'is brought into, operation at the same moment at which the air is discharged and acts on the pneumatically operating valves which control the passage of the substance into the cylindricalpressing chambers, an eleetrically operating valve which is brought into operation, after the measuring device has been emptied, to cause compressed airto'be delivered'trom the compressor and close the valves, controlling the admission of the substance into the cylindrical pressing chambers, at least two circuitclosing time switches performing the function of closing the electrical circuit of two corresponding motors and starting these motors to drive two corresponding pumps, of which one is a high pressure pump and the other is a low pressure pump (for the hydraulic fluid required for the hydraulically actuated plunger driving the filtering plate pistons, and for the cylinders with pistons for opening the pressure chambers) whereby the step of pressing the substance previously admitted to the pressing chambers is initiated, a pressure fluids distributor unit performing the function of controlling the passage of the fluid which acts on the hydraulic thrust plunger or plungers driving the pressing pistons ofthe various chambers, the discharge of this fluid and delivery into the cylinders of the hydraulically operating device for opening the pressing chambers during the step of expelling the cakes of pressed residual material when the pressing operation has been completed, and a so-called timing device adapted to be adjusted so as to come into operation at the predetermined time to close the electrical circuit supplying current to relays provided in the distributing unit to control the compressed air produced by the compressor.

With the object of reducing the speed of. the worldng stroke of the hydraulic plunger or plungers driving the I pressing pistons, a gauge is arranged on the ducts of the two high and low pressure pumps and is provided with an electrical contact adaptedto control the electrical circuit of the motor driving the low pressure pump, so as to stop this pump when the installation is to operate with the high pressure pump only, and this gauge is also provided with a second adjustable electrical contact for controlling the high pressure pum for the purpose of breaking the supply circuit actuating this pump, as soon as a predetermined pressure is reached.

The installation for manualor automatic operation, which is particularly suitable for hydraulic presses of the above-mentioned type, will now be more fully described with reference to one embodiment chosen solely by way of example and illustrated in the accompanying drawings; in these drawings, the installation is used with a press of the type having two symmetrical series each comprising a plurality of pressing chambers; this type has been devised by the applicants who also seek protection for this installation, and is more complicated than normal types of presses having a single series comprising a plurality of chambers.

The installation in question is illustrated in the accompanying drawings, in which:

FIGURES 1 and 1a, respectively, diagrammatically illustrate the whole of the installation, and the measuring device partly in vertical section and on a larger scale,

FIGURE 2 is a front view, in elevation, of the press by itself, and shows the control panel disposed between the two series each comprising a plurality of chambers,

I FIGURE 3 is a rear view, in elevation and on a larger scale, of the press shown in FIGURE 2, and shows only the first and last chamber of each one of the two series each comprising a plurality of chambers,

FIGURE 4 is a top plan view of the whole of the structure shown in FIGURE 3,

FIGURE 5 is a section on line 5-5 of FIGURE 4, and shows the device for distributing the fluid substance to be admitted to the cylindrical pressing chambers, and also the pneumatically operating valve devices for permitting admission of the fluid substance to those chambers,

FIGURE 6 is a top plan view of the structure shown in FIGURE 3, partly in section to show the cylinders with their respective hydraulic driving pistons with stepped rods for opening the chambers at the end of the pressing step in order to cause the cakes of residual pressed substance to fall out,

FIGURE 7 is a detailed view, partly in elevation, of the unit controlling the pressure fluids, which is accommodated in the body of the control panel of the installation,

FIGURE 8 is a view, from the. left-hand side, of the structure shown in FIGURE 7, showing the unit controlling the fiuids, and

FIGURES 9 and 0 show the wholeof the electrical system of the devices disposed in the various electrical circuitsfor automatic and for manual operation of the installation.

With reference to the accompanying drawings, A generally indicates a press (FIGURES 2 to 6) comprising two identical series of units a,, a and so on, with cylindrical chambers a for pressing the fluid substance.

b indicates the body for feeding the fluid through supply ducts 1 simultaneously to the two series of devices a and so on with a pneumatically operating valve for permitting or preventing entry of the fluid substances into the cylindrical chambers of each unit a a and so on.

d indicates the cylinders with hydraulic pistons 2. (FIGURE 6) for driving the surrounding rings 3 through the intermediary of stepped rods 4, to open the chambers a a and so on during the step of discharging the cakes (not shown in the drawings).

5 indicates the central body (FIGURES 5 and 6) of the press, which body is provided with two chambers 6 for the hydraulically actuated plungers 7 driving pistons 8 with filter plates 9 sliding in the respective cylinders 3 in the form of surrounding rings belonging to the respective series of multiple pressing chambers 11;, a and so on.

10 indicates two heads or uprights connected to the central body 5 by respective pairs of bars 11 of which the ends 11' are secured by corresponding threaded rings or nuts 12 and counter-rings or lock-nuts 13. 14 (FIG- URE 5) indicates an annular projection provided between the cylindrical chambers 6 and forming abutments for the plungers 7, and also a common inlet chamber 15 into which oil under pressure is admitted through a suitable orifice 16, for simultaneously actuating the two hydraulic plungers'7.

Now, with particular reference to the installation designed in accordance with the present invention (FIGURE 1), D indicates a measuring or pre-charging device for measuring the quantity of cocoa to be admitted to the pressing chambers of the press A operating automatically, when the working cycle has been started in this installation.

For this purpose, a pump P of the measuring device is actuated by an electric motor 17 directly connected to this pump, and takes material or cocoa mass from an agitator A through a pipe 18 and delivers this material through piping 19 to a cylinder 20 (FIGURE 1a); a'hollow piston 21 is axially slidably mounted in thevcylinder 20 and consists essentially of a further cylinder into which the substance is admitted and exerts a pressure so as to displace the piston 21 axially upwards.

A rod 22 rigid with the hollow piston 21 is slidable in a guide 23 on the cylinder 20; this rod has an adjustable member 24 arranged to come into contact with a corresponding switch member 25 rigid with the cylindrical wall 20 and adapted to break the circuit of the electric motor 17 and therefore to stop the action of the pump P when the measuring device is filled with the quantity of sub-. stance to be introduced, for pressing, into the respective pressing chamber a.

When the measuring device D is completely charged, the switch 25 stops the action of the pump P as mentioned above, whereby the charging of the measuring device stops. In the foregoing description it is assumed that initially the press was not in operation i.e. that the treatment of the fluid substance was about to begin; under these circumstances, when the charging of the measuring device stops after the predetermined capacity has been reached, it is necessary to act on a member which is disposed on the panel Q (FIGURE 2) and is one of the.

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control members and of which the nature will be further explained hereinafter; this member is adapted to establish automatic cyclic operation of the press.

Consequently, when the machine begins to operate automatically, and before the pump P is started for delivering the material from the measuring device D to the distributor b and from this distributor to the pressing chambers of the machine, the compressed air in the devices 0, c and c and so on, which control the valves admitting the material into the pressing chambers, is discharged; the discharge of this air is brought about by means of an electrically operated valve E (FIGURE 8) which controls the passage of the compressed air from the compressor C to valves of the devices 0; each device 0 has a pneumatically operated valve for the charging of each pressing chamber.

The circuit of the installation is made such that the pump P which charges the material into the pressing chambers, is started at substantially the same moment at which the air is discharged from the piping 27 conveying this air to the valves (FIGURE 3) which control the chambers for charging the pressing chambers.

It is desirable that the repetition of the working cycle of the measuring device, or rather the closing of the electric circuit which feeds the motor actuating the pump introducing the substance into the measuring device, should take place during the pressing step, so the operation of recharging the measuring device, and the steps taking place and finally leading to the discharge of the pressed cakes, will be suitably timed with respect to one another.

This process of closing the circuit is effected by means of a member in the form of a rod (FIGURE 4) rigid with a piston of the pressing chambers and provided with an adjustable member similar to the member 24 described with reference to the measuring device D so as to cause the working cycle of the measuring device to be repeated at the required time.

After the pump P for charging the material into the pressing chambers has extracted all the material contained in the measuring device D the return of the hollow piston 21 to the starting position causes a further stop member 24a, provided on the rod 22, to act on a resiliently mounted member 25a and thereby to break the circuit of the pump P which empties the measuring device D in order to charge the cylindrical pressing chambers.

In the meantime, the electrically operated valve E (FIGURE 8) comes into operation; this valve controls the piping 27 of the compressor C or rather, controls the valves of the charging devices 0 c and so on which are provided for each chamber for pressing the fluid substance, in such a manner that air is admitted into the compartments of the valves controlling the orifices through which the substance is admitted to each pressing chamber, and any further admission of the substance is prevented, that is to say the orifices for admitting the substance into the pressing chamber are closed.

At this stage it is necessary to begin the pressing step, that is to say, to advance the hydraulic plunger driving the pistons into the pressing chambers.

At this stage, two circuit-closing time switches 1' and 1'; (FIGURE are used; these switches perform the function of closing the electric circuit and starting the two motors m and 111 of the low pressure pump P and of the high pressure pump P respectively, and thereby beginning the step of pressing the substance previously in trodnced into. the pressing chambers.

The two. pumps P and P both deliver into one and the same pipe 28 (FIGURES 7 and 8) leading to the distributor casing C of. the pressure fluid unit G,

The distributor casing C performs the function of permitting the fluid to pass from the duct 28 to the duct 28a through the casing C From the duct 28a the fluid enters the rapid discharge casing S and acts on a ball 29 in a compartment 3% into which a duct 31 also leads.

Consequently, the fluid. compels the ball 29 to close the and in the meantime the fluid passes through a duct 32 leading to the central cavity 15 (FIGURE 5) and consequently the fluid acts on the hydraulic plungcrs 7 driv ing the pressing pistons 8 of the various chambers a.

In the particular instance in which the substance treated consists of cocoa in the fluid state, it is desirable to reduce the speed of the working stroke of the two hydraulic driving plunger-s 7. For this purpose, an electrical contact W is provided in a gauge Mg; (FIGURES 2 and 10) disposed on the control panel Q this contact controls the circuit of the motor m driving the low pressure pump P so as to stop this pump for the purpose of making the installation operate with the high pressure pump P only.

To ensure correct operation of the high pressure pump P the gauge M comprises an indicator adjustable to the limit pressure and provided with a member y adapted to break the supply circuit of the motor m of the high pressure pump P and thereby to stop the operation of the press, when this pressure is reached.

In this installation, the step of terminating the pressing operation can be effected in the following two ways.

Firstly, the step can be effected through the intermediary of a timing device, that is to say the duration of the pressing operation can be made dependent on a certain predetermined lapse of time, that is to say it can be a function of time; secondly and alternatively, it is possible to use, as a basis, the residual percentage of butter which is required to be left in the cakes of pressed cocoa beans, that is to say the duration of the-pressing operation can be made a function of the percentage weight of butter extracted.

As indicated hereinbefore, one way consists in providing a so-called timing device t (FIGURE 9) known per so, which may be adjusted to the required time and come into operation at that time, and which performs the function of coming into operation at a predetermined time so as to close the electrical circuit of the electrically operated pneumatic valve V which is actuated by means of relays r and. r (FIGURES 7 and 8).

The relays r and r perform the function of permitting the passage of compressed air produced by the compressor C which drives this air through piping 33' and 34 into a chamber 35 controlled by the electrically operated valve V and consequently causes the air to pass into a small double-action cylinder 36 which is' connected at 38, through the intermediary of a rod' 37, to a disc 39 which is rigidly connected, through a shaft 40, with an actuating member of the distributor casing C The distributor casing is adapted to permit passage of the fluid into one or the other of two ducts, that" is to say, either into the duct 28a which is used for actuating the hy draulic plunger-s 7 (FIGURE 6) orinto the duct 41 (FIGURE 7) which is used for admitting the fluid which acts on the plungers 2 (FIGURE 6) of the hydraulic cylinders d for displacing the surrounding rings 3' during the step of discharging. the cakes of pressed cocoa beans. In this position, the valve V can act' so. as to bring about the discharge step, that is to say, inth'e distributor casing C the fluid is diverted from the duct 28 into the duct 41. which. is used for acting. on the apparatus for discharging the cakes. 1

In the meantime, the fluid which is passing throughthe duct 41 is delivered both to the cylinders d for discharging the cakes, through the ducts 421 and 43 intercommunicating at 44, and also through a duct 45 so as to act on arod 46 (FIGURE 7) which rises and displaces the ball 29 which rises from its seat 31 and permits the oil contained in the cylinders of-the' hydraulic plungers 7 to discharge through the orifice 16, which communicates with these cylinders,- and to pass through the'comp'artment 3i and the duct 47, through the collectin-g head and-into amass? Y49 and thence to return to be re-circulated by the low and high pressure delivery pumps P and P The step of discharging the cakes has now been reached.

The installation is provided with a device which comes into operation, .during this discharge step, at the end of the stroke of the surrounding rings 3 which have been made to slide on their respective pistons 8, for the purpose of stopping the stroke of these rings at the limit of this stroke (FIGURE 4).

As has already been indicated hereinbefore, in this installation the step of terminating the pressing operation can be effected in two different ways, and it has also been indicated that the second way is based on the residual percentage of butter which is required to be left and which is required to be extracted. In conformity with this second way, the installation is provided with a balance 70 which is used for weighing the extracted butter,

that is to' say the butter which is progressively extracted during the pressing operation. Balance 70 has a manually settable pointer 71 and a movable pointer 72 responding to the weight of the butter discharged from receptacle 73 through pipes 74 into container 76. Pointers 71 and 72 have electric contact means 71a, 72a cooperating with each other when pointer 72 coincides with pointer 71. Contact means 71a, 72a preferably include a photocell. When a predetermined weight is reached this contact means comes into operation whereby the previously described electrically operated pneumatic'valve V actuated by means of the relays r and r is brought into action and causes the fluid to be discharged as described with reference to the first way.

The second way of terminating the pressing'operation has now been described and the description of the operation of the press at the end of the discharge step will now be continued. V p

The two innermost surrounding rings 3 (FIGURE 4) 'carry two members 54) and 51 in the form of rods each provided at its end, with an adjustable member 52 and 53 respectively, which members are each adapted to act on a switch 55 and 54 respectively, the switches being se- -cured to the stationary part of the machine, i.e. each to a respective one of the cylinders of the hydraulic plungers 7 in such a manner that when the surrounding rings 3 have reached their limit position after opening the chambers a for the extraction of the cakes the two switches 54 and 55 come into operation and act on an electrical circuit which is used for performing the following two operations.

' (1) The action of the two pumps P and P delivering fluid under pressure to the hydraulic pistons 7 cansing the surrounding rings 3 to slide, is stopped.

(2) The electrical circuit of the electrically operated valve V is closed; this valve, as stated previously, performs the function of returning the actuating member of the distributor C to the initial position, in which communication between the ducts 28 and 28a is established in order to produce the flow of the fluid which acts on the hydraulic plungers 7 driving the pistons 8 of the pressing chambers.

Under these circumstances, the working cycle can recommence. In order to prevent damage from occurring if for any reason one of the two devices for limiting the stroke of the surrounding rings 3 when moved for opening the chambers a and causing the cakes of cocoa beans to fall out, should fail to function, the in 'stallation is provided with a safety valve V (FIGURES 7 and 8) which is arranged on the duct 44, for the 'purpose of discharging the pressure liquid through a tube '56 leading into the collecting head 48 of the tube 49.

The springs 57 (FIGURE 6) were stressed during the step of discharging the cakes; when the discharge of the cakes has been effected, the pressure which previously acted on the surrounding .rings is no longer present, and therefore the springs 57 now return the surrounding rings 3 totheir original position, .re-establishing the cylindrical pressing chambers a and at the same time compelling the oil which is in the cylinders d and which acts on the pistons 2 actuating the surrounding rings 3, to return through the tubes 42 and 43m the duct, 41 and thence to the casing C and thence to the tube 58 leading to the head '48 and thence to the discharge duct 49.

A working cycle has thus been completed.

Moreover, in order to make certain that after the step of discharging the cakes has been completed. no further step of charging the cylindrical pressing chambers a can take place unless these chambers are completely closed, in order to make sure'that the compartments in question are tightly sealed, a further device is provided which operates at the end of the stroke of the surrounding rings 3 (FIGURE 4); this device is for instance provided on the first surrounding ring immediately adjacent to the head or upright 10 of the machine and operates at the end of the stroke; the device comprises a rod 59 having an adjustable member 69 similar to those described previously; the rod is rigid with the outermost surrounding ring 3a, and the member 60 as it advances comes into contact (when the corresponding chamber is completely closed) with a switch 61 provided on the frame It} or other stationary part of the machine, and actuates this switch so as to close the previously open circuit of the electrically actuated valve V (FIGURES 7 and 8) associated with the filling pump P which delivers the substance previously measured in the measuring device D and conveyed from that device to the cylindrical pressing chambers a through th respective charging devices c c and so on.

In order to obtain a' complete cycle in the shortest possible time, so that the operations can follow one another without taking up any more time than is necessary for completing each operation, that is to say, in order to avoid a situation in which the press is ready and its chambers are prepared for being filled but the material.

required for charging the chambers is not available, the measuring device I), is filled with the required quantity in the interval during the pressing step; for this purpose, a device similar to the'previously described devices on the rods 5% and 51 is provided for ensuring closure of the rings 3 of the chambers 11; this device consists of an adjustable member 62 (FIGURE 4) which is also mounted on the rod 51 and which advances during the working stroke of one of the main hydraulic plungers 7, that is to say the thrust or driving plungers, and the member 62 impinges against a switch 63 secured to the frame of the machine; this switch 63 causes the circuit of the electric motor 17 to be closed, which motor drives the pump P feeding the measuring device D whereby the device is charged.

It may be desirable to interrupt the automatic operation of the machine in order to perform some adjustment or other work that may be found necessary; for this purpose, the installation is provided with a device which immediately interrupts the operation of the machine at the instant when manual intervention takes place, and the machine may be controlled manually instead of automatically.

This device consists of a valve V interposed in the piping 33 and 34 (FIGURES 7 and 8) of the compressor C which supplies air to the electrically operated valve 'V which controls the small double-action cylinder 36, in such a manner that the valve V when actuated by hand firstly closes the duct 33, leading from this valve to the compressor, in order to prevent loss of pressure in the compressor itself, and secondly opens the duct 34, or rather, places this duct 34 in communication with the atmosphere, whereby the kinematic connection with the disc 39 is released and the disc 39 can be actuated by means of a hand wheel 64 keyed to the shaft 40 and adapted to be actuated by hand, thereby permitting the required control of the distributor casing C The installation also comprises an arrangement such that all the conductors of circuits of the various relays are connected to a single switch 65 which is actuated by hand at the moment when the automatic operation of the installation is to be interrupted.

After the above description it is now possible to summarize the steps making up a complete production cycle.

(1) The device D measuring the cocoa material is filled by hand (this is done only for the first pressing operation, and thereafter that device is filled automatically) At this point, automatic control is initiated simply by turning the switch. When automatic control is initiated, air is removed from the charging units, that is to say the orifices of the individual chambers are freed to permit the cocoa material to pass from the measuring device to the distributor and thence to the collecting tubes and thence into the chambers. At the same moment, the pump P takes the cocoa material from the measuring device and conveys this material into the individual containers, and the charging step is thus completed.

(2) When the discharging of the measuring device has taken place, that is to say, when the piston of the measuring device has descended to the end-of-stroke position, the electromagnetically operated valve is actuated which sends air from the compressor to the valves of the charging device b to cause the orifices of the pressing chambers to be closed.

The two adjustable starting time-switches start the two pumps, of which one has a pressure of three hundred kilogrammes per square centimetre and the other a maximum pressure of five hundred and fifty kilogrammes per square centimetre. The pump with a pressure of three hundred kilogrammes per square centimetre is switched olt by means of an electrical contact mounted in the gauge itself. Furthermore, as indicated hereinbefore, the gauge also has a manually adjustable extra safety contact which is normally adjusted to five hundred and seventy kilogrammes per square centimetre; this contact would operate it the maximum-pressure safety valves of "ofthe'timing device having a scale with a sixty-minute maximum and divided into minutes. If for instance the device is set to ten minutes, when this time has elapsed the timing device itself brings about the discharge of the press, that is to say the termination of the pressing operation.

After having caused this step to be performed, the timing device returns to zero and a further pressing operation will start when the press has been charged.

The timing device may be stopped by hand during the pressing step, and when the installation is restarted the timing device begins from the number of minutes which it showed before the manual intervention.

Moreover, when the pressing operation is finished, that is to say, when the set time has elapsed, the timing device closes an operating circuit of an electromagnetically actuated plug inserted in a container collecting the butter emerging from the press, and thereby causes the butter itself to be discharged at the same time.

(b) The press may be provided (for the purpose of calculating the weight of the butter which emerges, as previously indicated) with a balance 70 having a dial with hundred-gram graduations and readable with an accuracy of fifty grammes, and having a range of one hundred and thirty kilogrammes, and provided with a container 7 6 for collecting the butter.

As previously indicated, when the required weight is reached the photocell of contact means 71a, 72a directly controls the hydraulic means, causing the press to perform the discharge step, and at the same time closes the opcrating circuit of the electromagnetically actuated plug provided in the outlet of container 76 of the balance, so as to permit the extracted butter to leave the container; when the balance returns to zero, a second photocell 721; will open the circuit of the electromagnetic plug to per.- mit this plug to close the butter outlet.

During each pressing step, the measuring device will automatically be prepared by being charged with the correct quantity of cocoa material in readiness for the next pressing step.

(3) The discharge step takes place when pressing is terminated in dependency on time or on weight; removal of pressure, and initiation of the discharge step, take place under automatic control. This is efiected by the casing control unit, controlled by the double-acting pneumatic piston which reverses the pressing or discharge position through the intermediary of the solenoid-operated electric valve incorporated directly in the small pneumatic cylinder itself.

When pressing is completed, an electrical pulse derived either from the timing device or from the balance excites the electrically operated valve which controls the small cylinder and causes the hand-wheel to rotate from the pressing position to the discharge position.

At this moment, the liquid from the five hundred and fifty atmospheres pump, and also the liquid from the three hundred atmospheres pump which had been stopped by means of the contact on the gauge during the pressing step but which was automatically restarted during the discharge step, act on the extraction cylinders which proceed to discharge the cakes, stop the two'pumps and at the same time, by means of a pulse transmitted to the electrically operated valve of the cylinder mounted on the control unit, change the position to that of the preceding pressing step, thereby causing the extraction cylinders to discharge and producing hermetic closure of the cylindrical chambers a.

(4) The step of closing the cylindrical pressure chambers takes place at a time when pressing is completely finished; consequently, at the moment at which the containers close, air is removed from the discharge pistons and the pump is started which withdraws the cocoa material contained in the measuring device previously filled during the preceding pressing operation, and the cycle is repeated as previously described.

The distributor casing is designed to permit rapid discharge of the oil, that is to say, the pressure of the pumps passes through the casing but does not return in the discharge step, and passes directly from the central cylinder to the rapid discharge unit and thence to the casing of the pumps. This is for the purpose of avoiding unnecessary passage of quantities of oil through the control unit.

What I claim is:

1. An installation for the automatic operation of a hydraulic press in a continuous succession of working cycles, comprising at least one filter press including cylinder means, plunger means in said cylinder means, a plurality of coaxial telescopic press chambers having filter plates in the form of pistons operated by said plunger means, and ejector means for discharging material from said press chambers, a measuring device, a motor and a first pump for pumping a substance from an agitator into said measuring device, a device for interrupting the admission of the substance to said measuring device as soon as a predetermined quantity of the substance is contained in said measuring device, a second pump which withdraws the substance from said measuring device, a distributor supplied by said second pump and distributing the substance to said press chambers, a compressor, a pneumatically operating device having valves for controlling the admission of the substance to said press chambers, a control device operable to cause discharge of air from said compressor or to supply air to said operating device and adapted to become operative as soon as said measuring device has been fully charged by said gorges Ill first pump, an electrically operated valve actuated by said measuring device when the same has been emptied so as to cause compressed air from said compressor to close at the end of the plunger movement only said electric motor of said fourth pump are operative, said third pump being a low pressure pump and said fourth pump being a high pressure pump, a distributing unit supplied by said third and fourth pumps with an operating fluid and controlling supply and discharge of the operating fluid to said cylinder means of said press, an electric circuit including relays provided in said distributing unit and other relays controlling said pumps, and a timing device including switches in said circuit.

2. An installation as claimed in claim 1 including a gauge operatively connected to said high and low pressure pumps and including an electrical contact for controlling the electrical circuit of said motor of said low pressure pump to stop this pump when the installation is to operate with said high pressure pump only, and a second electrical contact for controlling the said high pressure pump and connected into the circuit of said motor of said high pressure pump to break said circuit when a selected working pressure is reached.

3. An installation as claimed in claim 1 wherein said measuring device comprises'two hollow bodies telescopically connected to each other, one of said bodies being stationary and the other body being movable in accord ance with the variations in volume of the substance introduced into said measuring device, the movable body of the measuring device being provided with a rod having a stop member, a switch actuated by said stop memher when all the substance has been Withdrawn from said measuring device, said switch starting said motor of said first pump when actuated by said stop member.

4. An installation as claimed in'claim 3 in which said control device comprises an adjustable member mounted on said rod for movement with said hollow body, a

corresponding member secured to the stationary body of said measuring device, and including switch'means operated by said adjustable member for breaking the circuit of said motor driving said second pump.

5. An installation as set forth in claim 3 and including a device fixedly connected to one of said filter plates of said press and being operative during the pressing movement of said plunger means, said last-mentioned device including switch means connected into the circuit of said motor which drives said first pump to recharge said measuring device so that the same is recharged when said filter plate is displaced.

6. An installation as claimed in claim 5 in which said first-mentioned device includes an electrically operated valve means.

7. An installation as set forth in claim 1 wherein said pressure fluid distributing unit comprises two distributor casings, one of said distributor casings being connected to said press for operating said ejector means and the other distributor casing being connected to said press for 12 operating said plunger means, said distributing unit hav-- ing rapid discharge means for the rapid discharge of the operating fluid after completion of the pressing stroke by said plunger means.

8. An installation as set forth in claim 7 and including a valve in said other distributing casing for controlling the operating fluid when the same is under pressure, said valve having a position blocking said rapid discharge means and-being controlled by operating fluid discharged from said cylinder means by said plunger means when 7 said ejector means are operative.

9. An installation as set forth in claim 7 and including a distributor member in said one distributor casing for controlling the passage of the operating fluid to said other distributor casing and to said plunger means.

10. An installation as claimed in claim 9 wherein said distributor member is manually operated.

11. An installation as set forth in claim 9 and including an operating device for operating said distributor member.

12. An installation as set forth in claim 11 wherein said operating device is controlled by said timing device.

13. An installation as set forth in claim 11 and including a balance for weighing the filtered substance and controlling said operating device.

14. An installation for the automatic. operation of a hydraulic press in a continuous succession of working cycles, comprising at least one filter press including cylinder means, plunger means in said cylinder means, and a plurality of press chambers having filter plates operated by said plunger means; a measuringdevice; a first pump for pumping a substance into said measuring device; a device for interrupting the admission of the substance to said measuring device as soon as a predetermined quantity of the substance is contained in said measuring device; a second pump for withdrawing a substance from said measuring device; a distributor supplied by said second pump and distributing thesubstance to said press chambers, an operating device having valves for controlling the admission of the substanceto said press chambers; a control device for actuating said-operating device and adapted to become operative as soon as said measuring device has been fully charged by said first pump; a means for closing said valves of said operating device and being actuated by said measuring device when the same has been emptied; a low pressure pump; a high pressure pump; two electric motors for driving said third and fourth pumps; at least two switches for closing the electric circuits of said two electric motors so that at the beginning of the plunger movement both said electric motors, and at the end of the plunger movement only said electric motor of said high pressure pump are operative; a distributing unit supplied by said third and fourth pumps with an operating fluid and controlling supply and discharge of the operating fluid to said cylinder means of said press; and means controlling said distributor unit.

Reitz July 21, 1936 Carver Aug. 9, 1955 

1. AN INSTALLATION FOR THE AUTOMATIC OPERATION OF A HYDRAULIC PRESS IN A CONTINUOUS SUCCESSION OF WORKING CYCLES, COMPRISING AT LEAST ONE FILTER PRESS INCLUDING CYLINDER MEANS, PLUNGER MEANS IN SAID CYLINDER MEANS, A PLURALITY OF COAXIAL TELESCOPIC PRESS CHAMBERS HAVING FILTER PLATES IN THE FORM OF PISTONS OPERATED BY SAID PLUNGER MEANS, AND EJECTOR MEANS FOR DISCHARGING MATERIAL FROM SAID PRESS CHAMBERS, A MEASURING DEVICE, A MOTOR AND A FIRST PUMP FOR PUMPING A SUBSTANCE FROM AN AGITATOR INTO SAID MEASURING DEVICE, A DEVICE FOR INTERRUPTING THE ADMISSION OF THE SUBSTANCE TO SAID MEASURING DEVICE AS SOON AS A PREDETERMINED QUANTITY OF THE SUBSTANCE IS CONTAINED IN SAID MEASURING DEVICE, A SECOND PUMP WHICH WITHDRAWS THE SUBSTANCE FROM SAID MEASURING DEVICE, A DISTRIBUTOR SUPPLIED BY SAID SECOND PUMP AND DISTRIBUTING THE SUBSTANCE TO SAID PRESS CHAMBERS, A COMPRESSOR, A PNEUMATICALLY OPERATING DEVICE HAVING VALVES FOR CONTROLLING THE ADMISSION OF THE SUBSTANCE TO SAID PRES CHAMBERS, A CONTROL DEVICE OPERABLE TO CAUSE DISCHARGE OF AIR FROM SAID COMPRESSOR OR TO SUPPLY AIR TO SAID OPERATING DEVICE AND ADAPTED TO BECOME OPERATIVE AS SOON AS SAID MEASURING DEVICE HAS BEEN FULLY CHARGED BY SAID FIRST PUMP, AN ELECTRICALLY OPERATED VALVE ACTUATED BY SAID MEASURING DEVICE WHEN THE SAME HAS BEEN EMPTIED SO AS TO CAUSE COMPRESSED AIR FROM SAID COMPRESSOR TO CLOSE 